Green State Joining Of ZrO₂-CePO₄ Ceramics

Green bodies of CePO4 and ZrO₂ were prepared by pouring prepared slurries into the plaster molds. Joined bodies were formed without interface at green state, followed by sintering without pressure. The ideal joints were obtained, and therefore the possibility of joining dissimilar ceramics in the green state without applied pressure and interface was proved. This technology will undoubtedly decrease the cost of complexly shaped or very large ceramic components manufacturing, and extend the application of advanced ceramic materials.Through analyzing the dispersant amount and the ball mixing time, effects of them on the property of slurries was analyzed, CePO4 and ZrO2 slurries with 1.0wt% dispersant will have the property of thixolrupy after 15 and 17 hours ball mixing, respectively. The result of the experimentation indicated: the green bodies which were made from the slurries having thixolrupy will have plasticity, so the bond strength of the joined bodies is so strong that can obtain ideal co-sintered bodies after sintering.Through measure of fracture toughness (KIC) of the joined bodies, the distribution of KIC was obtained. From the result, the KIC value of the joined varies with the position change. The more close to the distance to interface is, the smaller the KIC is, whereas, the lowest KIC didn't lay in the interface, but proximate interface.Three sorts of joining defects, cracks vertical to, parallel to and locating at the joining interface, were analyzed, which might be introduced by shrink stress, residual stress and poor process control, respectively. It was key factor to eliminate or control these defects for improving joining quality.The paper reports the joining mechanism, the plastic deform of matrixes will occur during sintering, therefore, the density of interspaces will diffuse from one matrix to another, atom would diffuse...